The present invention relates to a composition comprising a latex, more particularly a latex with acorn morphology, and a hydrophobically modified ethylene oxide urethane based rheology modifier (HEUR).
Stable aqueous dispersions of particle particles (latexes) characterized by a core-shell morphology wherein the core protuberates from the shell have been described. For example, U.S. Pat. No. 7,179,531 (Brown et al.) discloses a dispersion of multistage polymer particles characterized by a relatively small core portion protuberating from a relatively large shell portion of each particle, with the core portion being preferentially functionalized with TiO2-adsorbing groups. These so-called “acorn” particles are disclosed as being useful for preparing TiO2-polymer composite particles that provide dried coatings with improved hiding. WO 2013116318 A1 (Bohling et al.) discloses acorn dispersions with phosphorus acid groups concentrated at the protuberating core portion of the acorn, resulting in overall reduction in grit formation in a coating formulation.
The advantages of acorn technology in coatings formulations have yet to be fully explored and it would be desirable to determine the effects of this morphology on the efficiency of rheology modifiers such as HEURs.